
INTRODUCTION:
Thank you for purchasing this Infrared Thermometer. This is a non-contact infrared temperature measuring instrument.
Features include a 4 digits backlit LCD, scan/hold/auto function and auto power off (6 seconds). To measure a temperature,
point the unit at the desired object, pull the measuring trigger and hold till the end of the shot. Make sure the target area is
larger than the unit’s spot size.
IRT650
USER’S MANUAL
12 to 1 Wide-range Infrared Thermometer
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FEATURES:
• High performance for general purposes
• Emissivity adjustable from 0.1 to 1.00 in 0.01 steps
• Ultra low power consumption in shutdown mode
• Extended long time measuring reliability
• Laser sighting On/Off is switchable
• Backlit LCD display
• °F or °C selectable
• Electronic trigger lock
• Temperature data storage
APPLICATIONS:
• Manufacturing processes of semiconductor technology
• Automotive repair and maintenance
• Food safety and processing
• HVAC energy audits
• Electrical troubleshooting
• Testing terminals on circuits
• Scientific experiment
• Air conditioning
SAFETY INFORMATION:
Read the following safety information carefully before
attempting to operate or service the meter. Only qualified
personnel should perform repairs or services not covered in
this manual.
LASER WARNING NOTE!
Do not point laser directly at eyes.
Use caution around reflective surfaces.
Keep out of reach of children!
CAUTIONS!
DO NOT submerge the unit in the water.
This product is not designed for use in medical evaluations.
The product can only be used to measure body temperature
for reference. It is meant for industrial and scientific
purposes.
SAFETY SYMBOLS
Dangerous, refer to this manual before using the
meter.
CE Certification
This instrument conforms to the following standards:
EN61326: Electrical equipment for measurement, control and
laboratory use.
IEC61000-4-2: Electrostatic discharge immunity test.
IEC61000-4-3: Radiated, radio-frequency, Electromagnetic
field immunity test.
IEC61000-4-8: Power frequency magnetic field immunity
test.
Tests were conducted using a frequency range of
80-1000MHz with the instrument in three orientations.
The average error for the three orientations is ±1.0 °F
(±0.5 °C) at 3V/m throughout the spectrum. However,
between 781-1000MHz at 3V/m, the instrument may not
meet its stated accuracy.
The device may not be disposed in the trash. It
promotes the re-use recycling and other forms of
recovery of used materials and components, and to
improve the environmental performance of all operators
(manufacturers, traders, treatment facilities) involved in the
life cycle of products. Dispose of the product appropriately in
accordance with relevant regulations.
SPECIFICATIONS:
Distance/Spot Ratio: 12:1
Temperature Range: -25° to 999°F (-32° to 535°C)
Accuracy(@ ambient temperature of 77°F/25°C):
±5°F (±3°C) within -25° to -4°F (-32° to -20°C)
±3°F (±2°C) within -4° to 212°F (-20° to 100°C)
±2% within 212° to 999°F (100° to 535°C)
Thermopile: 5 ~ 14µm
Repeatability: ±2°F (±1°C)
Resolution: 0.1°F (0.1°C)
Response Time: 500 ms.
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Operating Temperature: 32° to 122°F (0° to 50°C),
10 to 90%RH
Auto Power Off: Automatically after approx. 6 seconds
Emissivity: Fixed at 0.95
°F/°C Switchable: YES
Backlight: YES
Laser Sight Switchable: YES
Dimensions: 6.69" x 5.23" x 1.77" (170 x 133 x 45mm)
Battery Type: “9V” battery
Battery Life: 16 hours
Weight: 5.8 oz. (163 g) Approx.
Accessory: “9V” battery, Instruction Manual,
Soft Carrying Case
OPERATIONS OF INSTRUMENT
QUICK START:
To measure a temperature, point the unit at the target that
you want to measure, pull the measuring trigger and hold. In
SCAN mode, the LCD displays either the current temperature
in Celsius or Fahrenheit.
The unit will HOLD the last reading for about 6 seconds after
the trigger is released; the word HOLD appears.
Be sure to consider the target area that is inside the angle of
vision of this instrument.
The single spot of laser is used for aiming only.
UNIT DIAGRAM:
LCD DISPLAY:
°F/°C AND BATTERY
CHANGE:
The unit is powered by
“9V” battery and displays
temperature in either
°F/°C. The user has to
replace the battery when
the battery voltage drops
below the voltage for
reliable operation and at
the same time the low
battery symbol will
appear. To change the
“9V” battery, pull and open the unit’s handle by using the
finger. Change the “9V” battery with a new one and push the
battery cover back in place.
TECHNIQUES OF INFRARED THERMOMETER:
FIELD OF VIEW (FOV) RATIO =
DISTANCE TO DIAMETER (DS) RATIO
The field of view is the angle of vision at which the
instrument operates and it is determined by the optics of the
unit. The FOV is the ratio of the distance from the target to
the target diameter. The smaller the target, the closer you
should be to it. When the target diameter
is small, it is important
to bring the
thermometer closer to
the target to insure that
only the target is
measured, excluding
the surroundings.
Display
Screen
Scan/Hold mode
indication
Laser on/off indication
Low battery
°F/°C indication
Temperature
indication
°F/°C switchable
Laser On/Off
“9V” battery
Laser
Sighting
Measuring
Window
Measuring
Trigger
Battery
and Cover
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EMISSIVITY:
Emissivity is the ability of an object to omit or absorb energy.
Perfect emitters have an emissivity of 1, emitting 100% of
incident energy. An object with an emissivity of 0.8 will
absorb 80% and reflect 20% of the incident energy.
Emissivity is defined as the ratio of the energy radiated by an
object at a given temperature to the energy emitted by a
perfect radiator at the same temperature. All values of
emissivity fall between 0.0 and 1.0.
Non-contact temperature sensors measure IR energy emitted
by the target, have fast response, and are commonly used to
measure moving and intermittent targets, targets in a
vacuum, and targets that inaccessible due to hostile
environments, geometry limitations, or safety hazard.
The cost is relatively higher, although in some cases it is
comparable to contact devises.
MAINTENANCE:
Cleaning the lens: Blow off loose particles using clean
compressed air. Gently brush remaining debris away with a
camel’s hair brush. Carefully wipe the surface with a moist
cotton swab. The swab may be moistened with water.
NOTE:
DO NOT USE SOLVENTS TO CLEAN THE LENS.
CLEANING THE HOUSING: Use soap and water on a damp
sponge or soft cloth.
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